"So, across much of the country we are seeing really dramatic improvement," he said. "It's just now with wildfires becoming more and more bigger every year and more frequent we are seeing a large part of the western U.S. an increase in the worst days of the year," said Jaffe.

Their research honed in on the PM2.5, the fine particulate matter in the air that the EPA considers unhealthy. The findings were just published Monday by the National Academy of Sciences.

"The take away from this, those seven days, the seven worst days each are getting worse and they're getting worse due to wildfire smoke," he said.

And those fine particles are so tiny you can't even see them with them -- they're not even as wide as a strand of hair," said Jaffe who said the particulate matter can be a danger to people with chronic disease, particularly respiratory conditions and to the vulnerable including the elderly.

"Particulate matter is bad -- it's analogous to smoking," said Jaffe.

He hopes his finding will impact forest management and encourage homeowners, particularly in rural areas to protect their homes from fire by eliminating fire fuels on their property, including; debris, dried brush and mosses. The DNR says it’s about creating defensible spaces around your home.

Jaffe says because of the poor air quality during wildfire season, homeowners may want to consider taking measures to keep smoke out of their homes.

No rain in sight this week may add even more fuel to the fire danger.

The Washington State Department of Natural Resource told us its crews have already responded to 650 wildfires this year, and worry hot temperatures and dry conditions could mean a long wildfire season.

Jaffe believes how crews manage fires and forests, human-factors and climate change are linked to an increasingly longer and more intense wildfire seasons in Washington.

"It's really sad because I know there is a connection between the wildfires the temperatures and the smoke," said Jaffe.

The worst air quality readings in our state were in eastern Washington.

The EPA says 35 microns of particulates is acceptable. The research found over 200 in Spokane on the worst day last summer.